Certainly, many of the dark side choices run counter to my personal ethics, but when I play I am playing from the point of view of my character. Because the situations are fictional, however much I personally would be appalled by a decision or act, I find that the fact that it is a game is an effective emotional buffer.

On my first couple of Imperial characters, I consistently chose the dark side options solely because they were dark side. I was curious to explore the game mechanics of progressing levels of dark side attunement, special item access and dark side corruption.

On my current characters, I am taking much more of a situation by situational approach. Playing my Sith Inquisitor on Hoth, for instance,

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I let the Ortolans continue to operate the power station, in spite of it being a light side choice. My character considered that this was an experienced labor force already fully qualified to operate and maintain the equipment and as aliens were suitable to such a menial role as custodians. To call in Imperial personnel would require these to be reassigned from other tasks to which they might be suited -- a waste of human resources.

But I don't make these decisions because I, personally, feel the alternative is wrong. A few times even on my Republic toons, even neutral decisions have been eye-openers from a moral perspective making me go, Seriously?. For example,

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many of the opportunities offered to my Smuggler to [Flirt] are in wildly inappropriate circumstances, such as with a stranded female starship pilot whose ship is falling into a sun.

But again, I am able to look at the situation and choose as my charcater would, or to explore the option that makes me personally curious as to the outcome.

I will say that the moral and philosophical principals on which the Sith Empire are built -- that power in the Force is a mandate to rule over those not so gifted, that warfare is a necessary source of cultural strength, that the weak should be enslaved etc. -- are starkly different from my own beliefs. But I am a roleplayer. I am pretending to be people who are different from me, with their own beliefs. And as they aren't actually torturing or blackmailing or murdering actual live people, I am okay with that.